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81.
This paper belongs to a series of applications of the Baccetti et al. formula (1) to the submicroscopical mathematical examination of human spermatozoa used for assisted reproduction. The present experiment concerns IVF, a technique requiring careful evaluation of sperm quality to predict the success of the program. Our results demonstrate that the sperm submicroscopic characters introduced in the formula are clearly correlated with the result of IVF. In fact the two numbers concerning sperm quality (percentage of spermatozoa free from structural defects and total number in the ejaculate of spermatozoa free from defects) obtained in successful and unsuccessful IVF groups, showed a large difference. Thet distribution in both cases reached a significance of 0.005. The synthetic parameters obtained are therefore a good tool in the prediction of sperm power in in vitro insemination techniques. The most important characteristics seem to be the quality of the acrosomal complex, the status of the chromatin, the shape of mitochondria, the axonemal pattern, and the membrane integrity. All these characteristics are expressed with largely different means in successful and unsuccessful ejaculates (t distribution significant at 0.005). All these data confirm that submicroscopic mathematical diagnosis offers a convincing evaluation of sperm structure and function, involving all organelles, including acrosome function and cell motility. It is also demonstrated that sperm quality is a major factor in the success of IVF and that it is clearly revealed by the integrity of the majority of the sperm organelles. An erratum to this article is available at .  相似文献   
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The degree of catabolism was studied in a group of seven patients with postsurgical acute renal failure, and net protein catabolism of 43.1 to 927 g/day. In 70% of a group of 30 patients with stable chronic renal failure receiving and 18 g high biological value protein diet, urea synthesis was equivalent to what could be accounted for by the protein content of the food. This equivalence was not found in studies in both adults and children who were treated for catabolic chronic renal failure. Data obtained show the superiority of feeding essential amino acids with an adequated caloric supply. The need for studies aimed at adapting the uremic patient to protein depletive mechanisms is strongly stressed.  相似文献   
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Small (60-90 μm) and large (100-130 μm) preantral follicles were isolated from adult mouse ovaries by a collagenase-dissection technique. These follicles were composed of resting oocytes surrounded either by granulosa cells, only, or by granulosa and undifferentiated theca cells. Further enzymatic dissociation of primary follicles yielded monodisperse cells characterized by abundant rough endoplasmic reticulum, microfilament-rich pseudopodia and only scant lipid droplets. These cells reaggregated, when explanted in stationary culture, forming epithelial cords and structures macroscopically reminiscent of native ovarian follicles. Anticipated association of follicular cells in epithelial-like monolayers was rare (≤ 10% of all cultured cells). Formation and growth of both follicle-like (FLS) and cord-like (CLS) structures occurred within 24 hours of culture, continued for 14 days, and was inhibited by cytochalasin B, but not by neuraminidase. FLS and CLS, as well as cell monolayers, underwent luteinization, as indicated by the presence in the culture medium of radioimmunoassayable progesterone and by frequent cytological features suggestive of active steroidogenesis. The present report indicates that (a) specific cell affinities exist among immature follicular cells which may play a role in folliculogenesis; and (b) follicular cells are endowed, from their early developmental stages with intrinsic steroidogenic capabilities which become pheno-typically expressed after escape from the intraovarian environment.  相似文献   
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Surgical approaches to postoperative mediastinitis that imply wire removal achieve earlier infection recovery but leave the patient with sternal instability. In 10 patients after wound surgical debridement, my colleagues and I achieved sternal synthesis by using Achilles tendons retrieved from multiorgan donors and stored in glutaraldehyde. Three tendons were used in each patient; they were passed through the bone at the manubrium and parasternally at the midsternum and the lower sternum. Thirty-day computed tomographic scan results, infection recovery, and quality of life were satisfactory.  相似文献   
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Extracorporeal photopheresis (ECP) may represent an alternative to immunosuppression, as a means of reducing rejection after thoracic organ transplantation. The mechanism by which ECP exerts its protective effects has, until now, remained elusive. We analyzed peripheral blood mononuclear cells of four children with chronic heart and lung transplant rejection, who received ECP in addition to conventional immunosuppressive treatment. The effects of ECP were evaluated at each cycle, comparing blood samples from the same patient collected before and after treatment. In vitro, peripheral blood mononuclear cells treated with ECP undergo apoptosis and are phagocytosed by immature dendritic cells, which, in turn, acquire a tolerogenic phenotype. The frequency of T cells, with a regulatory phenotype and strong suppressive activity, was significantly increased in the blood of ECP-treated patients. The immunomodulatory effects of ECP may be explained by its ability to increase the frequency of regulatory T cells with inhibitory action on transplant immune rejection.  相似文献   
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OBJECTIVE: This study aimed to assess extracellular matrix protein expression patterns at the convexity (right anterolateral wall) and the concavity of the dilated ascending aorta in patients with bicuspid aortic valve disease. METHODS: Aortic wall specimens were retrieved from the convexity and the concavity in 27 bicuspid aortic valve patients (12 with stenosis and 15 with regurgitation) and 6 heart donors (controls). Morphometry, immunohistochemistry, Western blot, and polymerase chain reaction were performed, focusing on matrix proteins involved in vascular remodeling. RESULTS: Type I and III collagens were significantly decreased in bicuspid-associated dilated aortas versus controls (P < .001), particularly at the convexity (P < .05 vs concavity). Expression of messenger RNA for collagens was lower than normal only in the regurgitant subgroup. At immunohistochemistry, proteins whose overproduction has been demonstrated in response to abnormal wall stress, such as tenascin and fibronectin, were more expressed in the convexity than in the concavity, especially in the stenosis subgroup. Tenascin, which is produced by smooth muscle cells in the synthetic phenotype, was nearly undetectable in controls. Fewer smooth muscle cells (stenosis, P = .017; regurgitation, P = .008) and more severe elastic fiber fragmentation (P = .029 and P < .001) were observed in the convexity versus the concavity. CONCLUSIONS: In bicuspid-associated aortic dilations, an asymmetric pattern of matrix protein expression was found that was consistent with the asymmetry in wall-stress distribution reported previously. Differences exist between patients with stenosis and those with regurgitation in terms of protein expression and content in the aortic wall. Further studies could clarify the relations between these findings and the pathogenesis of aortic dilatation in bicuspid aortic valve patients.  相似文献   
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